Billy Mitchell assembled the largest air fleet
ever committed to battle and established the Air
Service as a true combat arm.
The
St. Mihiel Salient
T
By Walter J. Boyne
reputation of airpower pioneer Billy Mitchell will be forever tied to the World War I
Battle of St. Mihiel, and that is as it should be. It was during that critical engagement in
France in September 1918 that the world got its first clear view of Mitchell’s developing
air­power creed.
The visionary airman believed that a nation should mass its airpower assets and concentrate
their use against the enemy right from the start of an engagement. This was true of observation, pursuit, and bombing aircraft alike. At St. Mihiel, Mitchell’s principles were applied
and vindicated, even if not to the degree that he might have wished.
In fact, the airpower portion of the battle of St. Mihiel was important more for its preparation
and planning than for its actual execution, which was hampered by poor weather. The future
of American airpower was charted in the way Mitchell and his staff planned the engagement
he
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AIR FORCE Magazine / February 2000
Billy Mitchell (leaning against a Spad at left above) gathered more than 1,400 American and Allied aircraft for the Battle of St.
Mihiel in September 1918. At left, among those at his command were 11th Bomb Squadron aircraft, shown in an impressive
lineup at Maulan, France, in 1918.
and in the gallant manner in which his equally inexperienced fliers fought it. It was a pattern
seen again and again in the decades to come.
“Aerial operations at St. Mihiel made the battle an important event in the history of US military aviation,” wrote Maj. Gen. John W. Huston, chief, Office of Air Force History, in the Air
Force’s official history of World War I. “It was, primarily, ... Mitchell’s show. He put together
the largest air force ever committed to battle and drew up the plan for its employment.”
Shock on the Western Front
In March 1918, German forces launched their last great offensive on the Western Front and
seemed destined to finally win the war. It was during this attack that US Army Gen. John J.
“Black Jack” Pershing lost his battle to keep the American Army together as a single entity under his command. So great was the Allied need that he had to allow piecemeal use of American
troops to stiffen French and British lines all the way through the Battle of Château–Thierry
in May and June 1918.
AIR FORCE Magazine / February 2000
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St. Mihiel Offensive Sept. 12–16, 1918
On the ground, the battle for the St.
Mihiel salient pitted AEF’s First Army—
three American corps and one French
corps—against 8.5 German divisions.
V Corps
Fresnes
Line of Sept. 16
River Meuse
Vigneulles
Line of Sept. 12
Thiaucourt
St. Mihiel
Pont-à-Mousson
IV Corps
Paris
St. Mihiel
II French Colonial Corps
I Corps
France
Because they thought a precedent
had been set, Pershing’s British and
French counterparts were taken aback
when he insisted that the American
Army fight the next battle as a unit
and under his command. Pershing’s
demand provoked a pointed argument
with Field Marshal Ferdinand Foch,
the Allied Supreme Commander in
Chief. However, the Pershing view
prevailed.
On Aug. 10, Pershing combined
his 16 US divisions into the US First
Army, which was supplemented by a
French army corps. He promised that
the American force would reduce the
German salient in the Allied line at
St. Mihiel. Each American division
had approximately twice as many
troops as French or German divisions,
but they lacked artillery and tanks,
which had to be borrowed from their
Allies. However, Pershing had no lack
of talent to depend on. Col. George
C. Marshall helped with planning.
Brig. Gen. Douglas MacArthur was
a brigade commander in the 42nd
(Rainbow) Division. Col. George
S. Patton Jr. commanded the 304th
Tank Brigade.
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The American Army would improve rapidly in the crucible of combat. Under Mitchell, the Air Service
would mature as rapidly—and suffer
a similarly horrendous casualty rate.
On Sept. 12, the First Army began
its five-day fight to reclaim the St.
Mihiel salient, which had been created almost by accident in the first
rush of the war. In late September
1914, the Germans had captured St.
Mihiel during an attempt to envelop
the fortress of Verdun. They failed in
this effort, and the salient remained
relatively quiet from that point on.
Rising terrain made the salient easy
for German forces to defend, but it
was too narrow for Germany to use
as a jump-off point for an offensive.
French forces made a minor attempt
to cut off the salient in 1915, but they
were repulsed.
The salient was 25 miles wide at
its base and 15 miles deep, extending from about 10 miles southeast of
Verdun to the town of St. Mihiel on
the Meuse River. The salient angled
eastward for 40 miles to Pont-àMousson on the Moselle River.
In the course of four years, the
German forces had diligently fortified the whole area with the usual
trenches, wire barricades, and concrete pillboxes in the front line,
backed up by a second line of similar
works. If the Allies broke through
all this, they would then be faced
with the Hindenburg Line, a heavily
wired series of trenches and strongly
built dugouts that the Germans had
equipped elaborately.
Behind the Hindenburg Line there
loomed the formidable fortress system of Metz and Thionville. The
salient was defended by 8.5 divisions
of ground troops, including a large
Austro–Hungarian element.
Despite these fortifications, Per­
shing readily agreed to have the
Americans try to pinch off the St.
Mihiel salient as the initial step in
a series of Allied offensives to end
the war. He was not an airman, but
Pershing believed that control of the
air was necessary, and he entrusted the
job to Mitchell. Mitchell was ready.
Mitchell’s formal estimates indicated that Germany would oppose
the American offensive with 2,000
aircraft. He insisted on gathering
as many airplanes as possible under
his command. (His estimate was for
effect; he had intelligence reports
showing that the enemy had 150
pursuit aircraft, 120 reconnaissance
aircraft, and 25 “battle airplanes”
[ground attack types] available.)
To the Offensive
Mitchell ordered the Air Service to
take the offensive at all points, with
the object of destroying the enemy’s
air service, attacking his troops on
the ground, and protecting its own
AIR FORCE Magazine / February 2000
date was breathtakingly short and
required immense effort on the part
of both the staff and the operational
units. The staff work generated in
preparation for the offensive was far
more sophisticated than Pershing had
any right to expect, given that air
warfare was itself new. Fortunately,
Mitchell had some top-notch staff.
The Germans flew the Fokker D.VII, the most advanced German single-seat fighter
to see action in World War I. It had been produced for a fighter competition in early
1918 and went into immediate production.
air and group forces. His planning
called for simultaneous strikes from
as many as 500 airplanes. The mass
formations were to alternate their
attacks on each side of the salient
in what he called “brigade tactics,”
never allowing the enemy to rest.
Mitchell eventually was given
command of 1,481 aircraft, though
not all were in service. It was the
largest air force ever assembled for
a single operation, consisting of
366 observation airplanes, 323 day
bombers, 91 night bombers, and 701
pursuits. Also on hand were 15 US
and six French balloon companies.
Of the total, the Americans would
provide about 40 percent of the
aircrews and aircraft, including at
least 288 Spad XIII pursuits, 144
Salmson observation airplanes, 54 de
Havil­l and DH-4 and 18 Breguet 14
observation airplanes, and 36 DH-4
and 18 Breguet 14 day bombers.
These were the nominal squadron
strengths and were supplemented by
additional staff and spare aircraft. The
other 60 percent of the aircrews and
aircraft belonged to French, British,
and Italian units.
France provided Spad XIII and
Spad XVI fighters, Salmson and
Breguet observation airplanes, and
Breguet/Renault bombers. Italy gave
30 Caproni Ca 450s to the bombing
effort. Both France and Italy placed
their units under Mitchell’s direct
command. The British, while cooperative, retained command of their
D.H. 4 and D.H. 9 day bombers and
AIR FORCE Magazine / February 2000
Handley Page night bombers but
used them against tactical targets in
support of the operation.
Mitchell insisted on secrecy. The
first mission of his pursuit units was
to deny the enemy any reconnaissance of areas behind the lines at
St. Mihiel while airfields and depots
were prepared. The Americans,
many on their first missions, were
very successful, and he was able to
move large numbers of aircraft into
several newly prepared airfields
without detection.
The time span from the authorization of the offensive and the kickoff
Detailed Planning
The plans were incredibly detailed.
They laid out exactly how the army
observation, corps observation, bombardment, and pursuit units were to
operate. These instructions included
everything from orders for daily
procedures to how formations would
be flown to the exact format of the
mission reports and the chain of command through which they would be
forwarded. There were even explicit
instructions on how pilots and observers were to conduct themselves
in case of capture.
The plans were also quite sophisticated in many respects. An extensive
radio warning network was set up to
monitor and report on enemy and
Allied air activity. A pursuit aircraft
was kept airborne over each of the
airfields at all times during the day,
an early use of the combat air patrol
intended to prevent any enemy reconnaissance airplane that had broken
through the barrier from learning of
the buildup. The logistics elements
were tasked to provide a special highgrade “fighting gasoline,” colored
red, for high-altitude work.
These Breguet aircraft on patrol sport American markings, but British, French,
and Italian units provided 60 percent of the crews and aircraft—most placed under
Mitchell’s command—used in the operation.
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Mitchell was farsighted in his
choice of operational commanders. The experienced Maj. Bert
M. At­k inson was selected as wing
commander, 1st Pursuit Wing. Maj.
Lewis H. Brereton was appointed
wing commander, Corps Observation Wing. Maj. John N. Reynolds,
a veteran of the 1st Aero Squadron’s
activities against Pancho Villa in
Mexico, became group commander
of the Army Observation Group. A
Canadian veteran of the Royal Flying Corps, Maj. Harold E. Hartney,
became commanding officer of the
1st Pursuit Group. There were many
other future luminaries at lower levels, including Eddie Rickenbacker.
Pursuit and bombardment aviation
were secondary to the observation
units in importance. This was true
in all armies during World War I,
because while aviation had not yet
gained the power to be decisive in
itself, aerial observation was crucial
for the successful conduct of both
artillery and infantry operations.
Observation and reconnaissance
were the primary tasks, with artillery
registration coming second to these.
The front was photographed daily,
with photo-interpreters checking to
see where artillery was emplaced,
the condition of the trenches, and
other near-term events. Sorties were
also flown deep behind enemy lines,
photographing and observing traffic
on roads and railways, checking the
activity at ammunition dumps, and
establishing targets for both day and
night bombardment operations.
Artillery registration—observing
the effect of battery fire and calling
in necessary changes—was hazardous
duty, for the job took long enough
for enemy pursuit aircraft to appear
on the scene and attack. There was
also the unseen but ever-present
danger of being hit by an artillery
shell in flight.
Communication to the ground was
done by means of radios, lights,
sound (klaxon or bursts of fire from
the machine gun), and weighted
message bags, the last proving to
be the most reliable. Radio communication from the ground was
generally more difficult, and reliance was placed on a coded series
of cloth panels or signal rockets or
flares and makeshift methods, such
as waving a handkerchief.
Composite Wings
The air arm’s bombardment aviation was assigned the task of destroying and harassing the rear areas of
the battlefield and attacking military
and industrial objectives beyond the
range of artillery. Given the primitive bombsights and sometimes total
lack of training, it’s not surprising
that German records record little
serious damage and few casualties.
Starting From Scratch
When the United States entered the Great War on April 6, 1917, the Army’s
Signal Corps Aviation Section had 55 aircraft, only half of which were in commission. None were worthy of combat as conducted on the Western Front.
The Aviation Section also possessed 65 officers and about 1,100 enlisted men
but had no plans for fighting or even preparing for a war. The American aviation
industry was virtually nonexistent. With the exception of the Curtiss Aeroplane
and Motor Co., there was no major supplier of aircraft, and an industrial base
from which to create one did not yet exist.
By the summer of 1918, however, the United States had established a new
and growing industry, with several plants mass-producing aircraft and engines.
Training facilities were thriving and the necessary industrial infrastructure was
being created.
All of the fruits of this effort would not be seen by the end of the war, but by
Nov. 11, 1918, thousands of aircraft had been built, thousands of pilots trained,
and an operating Air Service established.
Billy Mitchell’s rise to power was equally remarkable. He paid for his own flying training and, as a major, wangled his way to France as a military observer in
March 1917. Endowed with a diplomat’s charm and fluent in French, he ingratiated
himself with his counterparts in both the French and British air forces, including
the commander of the Royal Flying Corps, Maj. Gen. Hugh M. Trenchard.
Promoted to lieutenant colonel in May, and to colonel in August, Mitchell became the ranking US aviation officer in France—until the arrival of tough Brig.
Gen. Benjamin D. Foulois.
The two fought bitterly and Foulois won, becoming Chief of Air Service, American
Expeditionary Force. Yet Foulois had both the grace and the brains to recommend to Pershing that Mitchell be made Chief of Air Service, First Army—the
top combat position.
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Yet the bombers, like the observation
airplanes, were attractive targets for
enemy fighters. In another glimpse
of the future, Mitchell called for
composite wings, in which one or
more pursuit groups would always
be combined with one or more bombardment groups under a unified
command.
Pursuit aviation was intended to
secure air superiority, prevent enemy reconnaissance and bombing
airplanes from operating, and support
the troops with both reconnaissance
and strafing.
By Sept. 11, 1918, Mitchell had in
place the aircraft, people, tactics, and
plans for a major battle. He accepted
that many of the American units
were inexperienced, and he counted
on their numbers and enthusiasm to
carry the day. The only aspects of
the air battle that were not under
his control were the weather and the
enemy’s reactions.
The battle began at 0500 hours on
Sept. 12 after a blistering four-hour
artillery barrage of German positions.
The Germans were caught by surprise.
Bad weather halted Mitchell’s ambitious plans for an aerial offensive by
flights of several hundred aircraft.
Rain, high winds, and fog kept most
aircraft out of action as American
ground forces swept forward, doing
well in the center but being held up
on the flanks.
Instead, fighter and bomber aircraft
flew at low altitudes (some reports
indicate they never exceeded 50 meters) and strafed enemy trenches and
road traffic. It was extraordinarily
hazardous work, given the sheer mass
of artillery, machine-gun fire, and
rifle fire to which they were exposed.
There was little initial German air
opposition, a situation that would
change when the weather broke two
days later.
Headquarters relaxed all restrictions on flying in bad weather.
Missions were to be launched in
all but the thickest fog or heaviest
downpour. The mission reports of
those pilots who did get off the
ground cited balloons destroyed,
aircraft shot down, and roads shot
up. They were signed by names
that became familiar—Joseph F.
Wehner, Frank Luke Jr., Sumner
Sewall, Edward P. Curtis, Ralph
A. O’Neill, and Charles R. D’Olive
among them. The American ace
of aces at the time, Lt. David E.
AIR FORCE Magazine / February 2000
At the battle of St. Mihiel, Billy Mitchell (third from left in this photo taken in Germany, just after World War I) applied his principles of airpower—amass airpower
assets and concentrate their use on the enemy right from the start.
Putnam, credited with 13 victories,
was shot down and killed.
On the first day of battle, the
Americans flew 390 sorties and
dropped 14,300 pounds of bombs.
Although there were only 11 aerial
combats reported, there were two
unconfirmed victories. Among the
American airmen, 11 pilots and four
observers were listed as missing.
The weather remained bad on
Sept. 13. US troops began muscling
enemy forces out of the salient, and
the Americans began extensive use
of patrols of one or two aircraft to
do armed reconnaissance. There
was a moderate increase in enemy
aircraft, reflected in the 12 combats
out of 393 sorties. Nine pilots and
six observers came up missing. Two
enemy airplanes were confirmed
shot down, and there were claims
for five others.
The First Team
On Sept. 14, as Pershing’s First
Army slogged forward, two things
changed for Mitchell. The weather,
at last, was good, and the Germans
had moved in one of their best air
units, the Royal Prussian Jagdge­
schwader Nr. II, commanded by
Oberleutnant Freiherr Oskar von
Boenigk. Boenigk would score four
of his 26 victories in the Battle of St.
Mihiel. Jagdgeschwader II was made
up of four seasoned Jagstaffeln, each
commanded by veteran aces.
The units led by this formidable
crew were, for the most part, flying
AIR FORCE Magazine / February 2000
the Fokker D.VII, generally considered to be the best fighter airplane
of World War I.
By the third day of the offensive,
the American First Army had captured
15,000 enemy troops at the cost of
7,000 casualties. However, more than
250 heavy guns had been captured and
200 square miles of battered French
territory had been liberated.
As the weather improved, the attacks increased in intensity. By the
night of Sept. 16, the Americans had
flown a total of 2,469 sorties, engaged
in 145 aerial combats, and dropped
44,118 pounds of bombs. Claims for
52 victories were submitted, but most
of these were unconfirmed. Twenty
American aircraft were lost. The daily
casualty reports from the period are
misleading, in that they underestimate the number of persons killed in
action and overestimate the number
missing. An analysis of later reports
indicates that there were at least 40
crew members killed in action and
another 16 taken as prisoners of war.
It was a terrible toll to pay.
The American Air Service was
inexperienced and was undertaking
an ambitious campaign against the
veteran German air force. Most of
the units had not become operational
until June of 1918, with some not
achieving that status until the battle
had already begun. The pursuit units
were the most experienced of the
forces that Mitchell had at his disposal; proportionally, they suffered
the fewest losses of the battle. The
real lack of experience came in the
observation and bombing units. There
was only one bomber unit, the 96th
Bomb Squadron, in the line until Sept.
12, when it was joined by the 11th
and 20th. The observation airplanes
were considered by the Germans to
be the most valuable and the most
vulnerable, and they suffered the
heaviest losses.
“Despite handicaps of weather
and inexperience, the Air Service
contributed all in its power to the
success of this St. Mihiel operation,” said the official USAF history of the engagement. “The staff
was kept informed of developments
practically hourly by clear and
intelligible reports. The hostile air
forces were beaten back whenever
they could be attacked, the rear
areas were watched, photographed,
and bombed. Our airplanes participating in the battle, by the material
damage and confusion which they
caused, helped to increase the total
prisoners.”
There would be other battles in the
months to come, and more casualties
as well, but St. Mihiel had established the Air Service as a fighting
command, willing to take losses to
learn its job and able to take on both
aerial combat and ground attack duties. For the remainder of the war,
the observation airplanes and the
bombers continued to take the most
losses against German opposition,
which began to weaken only in the
latter part of October.
The Battle of St. Mihiel became a
signature note for Col. Billy Mitchell
in his long, and ultimately successful,
crusade to create a powerful independent Air Force. It also established an
Air Force tradition that whatever the
odds and whatever the opposition, no
mission would ever be turned back. ■
Walter J. Boyne, former director of the National Air and Space Museum in Washington, is a retired Air Force colonel and author. He has written more than 400
articles about aviation topics and 29 books, the most recent of which is Beyond
the Horizons: The Lockheed Story. His most recent article for Air Force Magazine,
“The Rise of Air Defense,” appeared in the December 1999 issue.
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